The present invention is directed to bicycle sprockets and, more particularly, to a bicycle sprocket having recesses formed on a lateral side surface of the sprocket.
It is often desirable to construct bicycle sprockets as lightweight as possible to help reduce the overall weight of the bicycle. Furthermore, mountain bicycles are often ridden in very muddy terrain. As a result, mud tends to build up between the sprocket teeth, thus interfering with proper meshing of the chain with the sprocket teeth.
JP 1-41675 discloses a sprocket formed from a very thin plate with recesses formed on both lateral sides of the sprocket. The very small thickness of the plate and the recesses on both lateral sides of the sprocket tend to weaken the sprocket, so the sprocket is formed with an undulating cross sectional shape to add strength. Forming such an undulating shape complicates the manufacturing process, and the sprocket is still relatively weak.
JP 50-39941 discloses a sprocket having cutout portions adjacent to each sprocket tooth in addition to chamfers on both lateral sides of the sprocket. The cutout portions tend to weaken the load carrying ability of the sprocket teeth, and the recesses further weaken the sprocket body. Thus, it is still desirable to have a sprocket that has sufficient strength while also preventing buildup of contaminants between the sprocket teeth.